基于联合物种分布模型的呼伦贝尔草地退化评价及未来潜在风险预测

草地退化已经成为全球最严重的环境问题之一，我国天然草地的80%分布干旱和半干旱地区，近年来绝大部分出现了不同程度的退化，从而带来了一系列的生态环境问题，草地退化状况评价及其对气候变化的响应已成为旱地生态系统研究的热点问题之一。本研究以呼伦贝尔草地为研究对象，采用野外样地调查数据对不同环境梯度下草地退化指示种（群）进行分析，将分析结果与降尺度全球环境数据相结合，采用隐变量模型和入侵种模型相结合的方法，构建该区草地退化指示种（群）分布模拟的联合物种分布模型，对指示种（群）的空间分布进行模拟，进而对不同气候变化情景下指示种的分布进行预测；基于模型生成的指示种（群）的模拟和预测图，建立草地退化评价指标体系，并对该区草地退化的现状及未来潜在风险进行评价，研究结果将为呼伦贝尔草地退化的防治奠定理论基础和实践参考，同时也可为相似区域的草地退化评价提供科学可靠的方法。

Rangeland degradation has been a global environmental problem. About 80 percent of rangeland in China distributes in dryland, majority of them is under the degradation, resulting in a series of ecological and environmental aftermaths. The assessment of rangeland degradation and its response to climate change has been a hotspot in dryland ecosystem research. This project, using large amount of commnity sampling data in Hulun Buir Sandland, quantifies indicator species (group) of rangeland degradation along the environmental gradients, then integrating sampling data with downscaling global environmental datasets, latent variable models and invasive species distribution models are used to build a multi-species joint species distribution model for predicting and simulating indicator species distribution, and for projecting indicator species distribution under multi-scenarios of climate change. On the basis of simulated and projected maps of indicator species, an indicator assessment system of rangeland degradation is established to evaluate the status of rangeland degradation and its potential risk in future. The project results will provide theotical foundation and practice methods for fighting against rangeland degradation in Hulun Buir Sandland, as well as methodology for rangeland degradation assessment in similar dryland areas.